Write down concept of Barkhausen conditions for sustained oscillations.

Explanation

Barkhausen conditions for sustained oscillations
The following condition called Barkhausen conditions should be satisfied for sustained oscillations in the oscillator.
• The loop phase shift must be `0^(@)` or integral multiples of `2pi`
• The loop gain must be unity. `|AbetaI` - 1
Here, `Ato`Voltage gain of the amplifier,
`bto`feedback ratio, (fraction of the output that is fed back to the input)